DE102022102604A1 - Relative twist detection device and crank assembly - Google Patents

Abstract

Device (10) for detecting a relative rotation between a first rotating section (12) and a second rotating section (16), which are spaced apart from one another in a longitudinal direction (20), the first rotating section (12) being rotatable about a first axis (14). , which is arranged parallel to the longitudinal direction (20), the second rotary section (16) being rotatable about a second axis (18), the first rotary section (12) and the second rotary section (16) being connected via at least two first coupling elements (24 ) are coupled to each other, which are essentially inelastic in the longitudinal direction (20) and at least one of which is arranged neither coaxially with the first axis (14) nor coaxially with the second axis (18), such that a relative rotation of the first rotary section (12) and the second rotary section (16) necessarily leads to a relative axial offset (A) between the first rotary section (12) and the second rotary section (16), and with a sensor arrangement (26) that detects the axial offset (A).

Description

The present disclosure relates to a device for detecting a relative rotation between a first rotary section and a second rotary section which are spaced apart from one another in a longitudinal direction, the first rotary section being rotatable about a first axis which is arranged parallel to the longitudinal direction and the second rotary section is rotatable about a second axis.

Furthermore, the present invention relates to a pedal crank arrangement for a human-powered vehicle, which has a first crank, a second crank and a detection device of the type described above, the first crank being non-rotatably connected to the first rotary section.

An example of a transducer for measuring torque in a rotating shaft is from document WO 99/05493 known.

The document DE 10 2008 027 719 A1 discloses an inductive torque sensor that is installed stationary relative to a vehicle and is designed without wiper springs. In this case, two circuits are arranged, to which two different angles to be determined are assigned.

The document EP 2 386 844 A1 discloses a torque sensor having first and second rotary members. The first rotating part is configured to apply a torque force thereto. An elastic transmission element is arranged between the first rotating part and the second rotating part. The first rotary part twists relative to the second rotary part as a function of the torque force applied by a twist angle that can be measured and assigned to the torque force.

The document DE 10 2018 107 416 A1 discloses another device for determining an angle of rotation and/or a torque.

The document DE 10 2020 100 319 A1 relates to a rotation angle sensor for determining a rotation angle and/or a torque.

In the field of motor assisted bicycles (e-bikes), it is desirable to sense the torque applied by a rider to a pedal crank assembly. This torque request from the driver can then be used to control the supporting electric motor.

Current systems on the market either use a pick-off to pick up the signal from a torsion shaft, or recognize an angular misalignment of a torsion shaft, which is converted into a torque. In order to operate such systems, it is often necessary to place sensor disks on the axle, which have a significantly larger radius than the torsion shaft itself.

Another way to get a non-contact signal is to measure the stress on a ferrite shaft. Here, the magnetic flux is measured and the change is converted into a torque. The prerequisite for this is that the torsion shaft is made of a ferritic material. In addition, it is necessary to create a significant strain in order to obtain an adequate signal.

Against this background, it is an object of the present disclosure to provide a device for detecting a relative rotation between a first rotating section and a second rotating section, which can be constructed in a structurally simple manner and in a compact manner.

The above object is achieved by a device for detecting a relative rotation between a first rotating section and a second rotating section, which are spaced apart from one another in a longitudinal direction, the first rotating section being rotatable about a first axis which is arranged parallel to the longitudinal direction, the second rotating section can be rotated about a second axis, the first rotating section and the second rotating section being coupled to one another via at least two first coupling elements which are essentially inelastic in the longitudinal direction and at least one of which is neither coaxial to the first axis nor coaxial to the second Axis is arranged such that a relative rotation of the first rotary portion and the second rotary portion forcibly leads to a relative axial displacement between the first rotary portion and the second rotary portion, and with a sensor assembly that detects the axial offset.

The basic idea of the present detection device is consequently to form a type of rotation/translation converter which converts a relative rotation between two rotating sections into a relative axial offset between the two rotating sections. This takes place via at least two first coupling elements, via which the two rotary sections are coupled to one another. The coupling elements are designed to be essentially inelastic in the longitudinal direction, so that a fixed relationship can be achieved between a relative rotational offset and a relative axial offset. At least that coupling element which is arranged neither coaxially with the first axis nor coaxially with the second axis is preferably designed as an elastically deformable bending element which is elastically bent when the two rotary sections rotate relative to each other. Due to the fact that the coupling element is designed to be inelastic in the longitudinal direction, this bending inevitably leads to a relative axial offset of the two rotary sections. Due to the fact that the coupling element is designed to be elastic in the bending direction, an automatic return to a basic position takes place when a force for generating a relative rotation between the rotary sections is interrupted. The basic position is a defined relative position between the two rotary sections, in particular a defined relative rotary position.

The rotary sections can be shafts, for example, which are rotatably mounted on a housing. The rotating sections can be made of any material and in particular do not have to be made of a ferritic material. For example, the rotating portions may be made of metal, such as a metal suitable for making shafts, such as steel.

The sensor arrangement, which detects the axial displacement between the rotary sections, can be arranged in the radial direction close to the outer circumference of the rotary sections. The sensor arrangement preferably includes a sensor element, which is rigidly fixed, for example as a ring element, to one of the rotary sections, and a second sensor element, which detects an axial displacement of this first sensor element. Overall, a compact design can be realized in this way.

Preferably, in the device for detecting a relative movement, one of the two rotary sections is axially fixed, so that the relative axial offset is an axial movement of the other rotary section relative to the axially fixed rotary section. It goes without saying that in this case the sensor arrangement is assigned to that rotary section which is not axially fixed but is movably mounted in the axial direction.

In general, the disclosed detection device can be used for a large number of applications, namely wherever a torque introduced into a shaft is to be measured.

A preferred application is a pedal crank assembly for a human-powered vehicle, particularly a bicycle, having a first crank, a second crank and a sensing device of the type disclosed.

Typically, the two cranks are connected to a first shaft (crankshaft) that is non-rotatably connected to one of the two rotary sections. A further shaft, which is connected to the other rotating section or, if the detection device has a third rotating section, is connected to this, can be rigidly connected, for example, to a chainring which is connected to a driven wheel of the vehicle via a chain drive or another Traction means (toothed belt) is connected. In this case, a torque is introduced into one of the rotating sections, specifically via one of the cranks and a crankshaft connected thereto. The torque is supported via an output on the other rotating section, so that the rotating sections are rotated relative to one another. This rotation corresponds to a torque that is introduced into the pedal crank arrangement and that is ultimately measured by the sensor arrangement of the detection device, ie by measuring a relative axial offset of the rotary sections.

The vehicle powered by muscle power can be assisted by an electric motor. The power provided by an electric motor can be introduced into a drive member that is connected to the first rotating section or the second rotating section (or to a third rotating section if the detection device has a third rotating section).

The first rotating section and the second rotating section preferably have an axial distance of more than 10 mm and less than 60 mm, in particular from 10 mm to 30 mm, in particular from 15 mm to 25 mm.

This axial distance essentially corresponds to the axial length of the first coupling elements when they are aligned parallel to the longitudinal direction.

The number of first coupling elements is preferably greater than 4 and less than 25, in particular greater than 6 and less than 20, preferably greater than 6 and less than 16, and in particular in a range from 8 to 12.

It is particularly preferred if all the first coupling elements are arranged neither coaxially to the first axis nor coaxially to the second axis.

The first axis and the second axis are preferably coaxial with one another, but can also be offset parallel to one another.

The first rotating section and the second rotating section can preferably be within one Rotate angle ranges that are larger than 5° and smaller than 65°. The angular range over which the rotary sections can be rotated relative to one another is particularly preferred in a range from 30° to 60°.

The maximum angle of rotation can either result from the maximum inherent elasticity of the coupling elements, but can also be set up by a stop for the angle of rotation.

A maximum relative axial offset in a range from 5 mm to 25 mm, preferably in a range from 10 mm to 25 mm, preferably results from the rotary sections connected to one another via the first coupling elements.

It goes without saying that the above-mentioned dimensions and figures refer to a connection of the detection device in a pedal crank arrangement of a bicycle or the like. In the case of other connections, other dimensions may also be preferred, depending on the torques that occur and other boundary conditions.

The first and/or the second rotary section are preferably each mounted on a housing by means of a radial bearing, which can be, for example, a roller bearing. One of the rotary sections is also preferably mounted axially, ideally by the same bearing, which is designed as a radial/axial bearing, for example. The other rotary section is preferably mounted in an axially displaceable manner.

The task is thus completely solved.

It is particularly preferable if the first coupling elements each have a first end that is fixedly connected to the first rotary section and a second end that is fixedly connected to the second rotary section.

It is particularly advantageous if the first ends of the first coupling elements are arranged on a circle coaxial with the first axis and/or if the second ends of the first coupling elements are arranged on a circle coaxial with the second axis.

The circle on which the respective ends of the coupling elements are arranged can, for example, have a diameter in a range from 10 mm to 25 mm, in particular in a range from 12 mm to 20 mm.

This information also relates to a preferred application in a pedal crank arrangement.

In the detection device described so far, one of the rotating sections is preferably clamped in an axially fixed manner, and the other rotating section is mounted so that it can be displaced in the axial direction. This can entail additional construction costs, in particular when the axially displaceable rotary section is to be connected to other elements in a pedal crank arrangement or the like. Storage can also be more complex, particularly on the side of the other rotary section.

According to a particularly preferred embodiment, the detection device therefore has a third rotating section which can be rotated about a third axis which is arranged parallel to the longitudinal direction and which is coupled to the second rotating section via at least two second coupling elements which are essentially inelastic in the longitudinal direction and at least one of which is arranged neither coaxially to the third axis nor coaxially to the second axis, such that a relative rotation of the third rotating section and the second rotating section necessarily leads to a relative axial offset in the longitudinal direction between the third rotating section and the second rotating section .

In this embodiment, it is possible to firmly clamp both the first rotating section and the third rotating section in the axial direction, ie to mount them axially. In addition, the first and the third rotary section in this exemplary embodiment are preferably mounted radially on a housing by means of radial bearings. In this preferred case, the second rotary section is mounted so that it can move freely between the first and the third rotary section. The second rotating portion is connected to the first rotating portion through the first coupling members and to the third rotating portion through the second coupling members. In this case, the sensor arrangement is still assigned to the second rotary section.

In this embodiment, a relative rotation between the first and the third rotating section inevitably leads to an axial offset of the second rotating section, which can be detected by means of the sensor arrangement.

In this embodiment, a relative rotation between the first rotating section and the third rotating section is consequently detected, specifically by detecting an axial offset of the second rotating section.

In some embodiments, the second rotating section can be rotated relative to the first rotating section or the third rotating section. In other embodiments it is however, it is conceivable that the second rotary section does not rotate relative to each other when the first rotary section and the third rotary section rotate relative to each other. This applies in particular when the coupling of the second rotating section and the first rotating section via the first coupling elements and the coupling of the second rotating section and the third rotating section via the second coupling elements are designed symmetrically in relation to a radial plane that runs through the second rotating section.

According to a particularly preferred embodiment, the second coupling elements each have a first end that is firmly connected to the third rotary section and a second end that is firmly connected to the second rotary section.

It is particularly advantageous here if the first ends of the second coupling elements are arranged on a circle coaxial with the third axis and/or if the second ends of the second coupling elements are arranged on a circle coaxial with the second axis.

The diameter of the circle of the second coupling element is preferably identical to the diameter of the circle of the first coupling element.

The third axis is preferably coaxial with the second axis and coaxial with the first axis. In other words, the three rotating sections are all arranged coaxially to a uniform axis.

The coupling elements can generally have any shape. However, it is particularly preferable if the first coupling elements are first rod-shaped elements and/or the second coupling elements are second rod-shaped elements.

The rod-shaped elements can, for example, have a diameter in a range from 0.5 mm to 5 mm, preferably in a range from 0.8 mm to 2.5 mm.

The coupling elements are preferably made of spring steel. The connection to the rotating sections can be made in any way, for example by welding. In further variants, the coupling elements are each formed in one piece with the respective rotary section, for example by means of 3D printing (“additive manufacturing”).

The coupling elements in the form of rod-shaped elements can each be aligned parallel to the longitudinal axis in a basic position.

However, it is particularly preferable if the first rod-shaped elements are each arranged skewed at a first oblique angle to the first axis and to the second axis in a basic position and/or the second rod-shaped elements in a basic position are each skewed at a second oblique angle to the third axis and are arranged to the second axis.

As a result, the coupling elements already have a skewed position in the basic position, so that changes in the angle of rotation lead directly to a larger axial offset.

The first oblique angle and/or the second oblique angle can preferably be in a range of 5° to 30° in relation to the longitudinal axis.

It goes without saying that the deflection in the form of a relative rotation corresponds to a deflection starting from the respective basic position, ie starting from positions in which the first rod-shaped elements are already arranged at an angle.

It is also particularly preferable if the first coupling elements and the second coupling elements are designed to be essentially mirrored in relation to a radial plane that runs through the second rotary section, such that the first rotary section and the third rotary section can be rotated relative to one another. without the first rotary section and the third rotary section being forcibly displaced axially relative to each other.

In this embodiment, as described above, the first rotary portion and the third rotary portion can be axially supported.

The sensor arrangement can be designed in any way as a displacement sensor.

It is particularly preferable if the sensor arrangement has a first sensor section and a second sensor section, the first sensor section being fixed to the second rotary section and the second sensor section being fixed to a housing.

The first sensor section preferably has a magnet, in particular in the form of a ring magnet, which is arranged coaxially around the axis of the second rotary section.

The second sensor section has at least one Hall sensor or an inductive sensor, which is preferably arranged fixed to the housing and which detects an axial displacement of the first sensor section.

In this case, the second sensor section preferably has at least two sensor elements which are arranged on axially opposite sides of the first sensor section.

As a result, the detection can be carried out with a high degree of certainty.

It is particularly advantageous if the two sensor elements are connected in a bridge circuit.

Here, the signal for detecting the axial offset can be amplified.

According to a further preferred embodiment, the first sensor has an incremental section, by means of which a rotation of the second rotary section can be detected.

In this embodiment, it is not only possible to use the detection device to detect a relative rotation of the first rotating section and the second rotating section. Rather, it is also possible to detect an angular velocity and consequently a relative rotational position of the second rotating section, and since this is connected to the first and third rotating sections over a limited angular range in the direction of rotation, also to detect an angular speed of these rotating sections.

An outer circumference of a ring-shaped magnet is preferably designed in the manner of a gear wheel or the like.

A rotational speed of the rotary sections can be detected via the angular velocity. In some cases, an absolute rotary position can also be detected. In particular, when a rotational position of a crank of a pedal crank arrangement is known and the incremental encoder assumes a fixed rotational position in relation to that crank, an absolute rotational position of that crank can also be inferred via an incremental encoder.

It goes without saying that the features mentioned above and those still to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

• 1 eine perspektivische Teilansicht einer Ausführungsform einer Tretkurbelanordnung mit einer Vorrichtung zur Erfassung einer Relativverdrehung;
• 2 eine Längsschnittansicht durch die Tretkurbelanordnung der 1 in einer Grundposition;
• 3 eine Schnittansicht entlang einer Linie III-III in 2;
• 4 eine Längsschnittansicht durch die Tretkurbelanordnung der 1, nach einer Relativverdrehung von zwei Drehabschnitten;
• 5 eine Schnittansicht entlang einer Linie V-V in 4;
• 6 eine perspektivische Ansicht einer weiteren Ausführungsform einer Tretkurbelanordnung mit einer weiteren Ausführungsform einer Vorrichtung zur Erfassung einer Relativverdrehung;
• 7 eine Längsschnittansicht durch die Tretkurbelanordnung der 6 in einer Grundposition;
• 8 eine Schnittansicht der Tretkurbelanordnung der 6 und 7 nach einer Relativverdrehung von zwei Drehabschnitten; und
• 9 eine schematische Darstellung einer Sensoranordnung für eine Erfassungsvorrichtung.

Embodiments of the invention are shown in the drawing and are explained in more detail in the following description. Show it:

• 1 a perspective partial view of an embodiment of a pedal crank assembly with a device for detecting a relative rotation;
• 2 a longitudinal sectional view through the pedal crank assembly 1 in a basic position;
• 3 a sectional view taken along a line III-III in 2 ;
• 4 a longitudinal sectional view through the pedal crank assembly 1 , after a relative rotation of two rotary sections;
• 5 a sectional view taken along a line VV in 4 ;
• 6 a perspective view of a further embodiment of a pedal crank assembly with a further embodiment of a device for detecting a relative rotation;
• 7 a longitudinal sectional view through the pedal crank assembly 6 in a basic position;
• 8th a sectional view of the pedal crank assembly 6 and 7 after a relative rotation of two rotary sections; and
• 9 a schematic representation of a sensor arrangement for a detection device.

In the 1 until 5 shows a first embodiment of a pedal crank arrangement T for a vehicle, in particular a bicycle, in particular an e-bike, with a first embodiment of a device 10 for detecting a relative rotation of two rotary sections.

The pedal crank arrangement T includes a first crank K1 and a second crank K2, which are offset in a manner known per se by 180° with respect to a pedal crank shaft, not shown in detail. A preferred direction of drive rotation is denoted by R. The driving direction of rotation R is the direction in which the pedal crank assembly is rotated to propel the associated vehicle. As a rule, a direction of rotation opposite to the direction of rotation of the drive is also possible due to a freewheel or the like, but without influencing the drive of the vehicle.

The detection device 10 includes a first rotary section 12 which is arranged coaxially to a first axis 14 and is mounted radially on a housing 34 by means of a first radial bearing 15 . Furthermore, the detection device 10 includes a second rotary portion 16 which is arranged coaxially to a second axis 18 and by means a second radial bearing 19 is mounted radially on the housing 34.

The first axis 14 and the second axis 18 are aligned parallel to a longitudinal direction 20 which is parallel to a pedal crank axis. In the present case, the first axis 14 and the second axis 18 are arranged coaxially with one another, but can also be arranged offset with respect to one another.

The first rotary section 12 is also supported axially, namely by means of a schematically indicated axial bearing 22, which has, for example, a shoulder on the first rotary section 12 and an axial locking ring that engages in a groove of the first rotary section 12, the first rotary section 12 being connected to a first Part of a radial bearing 15 is rigidly connected, which is defined between the shoulder and the axial locking ring. The radial bearing is preferably a roller bearing that can also absorb axial forces. A second part of the radial bearing 15 is firmly fixed to the housing 34 of the detection device 10 in the axial and radial directions. The housing 34 can also be a housing of the pedal crank assembly T.

The second rotary section 16 is supported radially with respect to the housing 34 by means of the second radial bearing 19 , but is supported in an axially displaceable manner with respect to the housing 34 .

The first rotary section 12 is, for example, non-rotatably connected to a first crank K1.

In the 1 - 5 the second rotary section 16 is connected to the second crank K2 of the pedal crank assembly T. In other cases, however, the second rotary section 16 can also be non-rotatably connected to a further shaft of the pedal crank arrangement, the further shaft being connected, for example, directly or indirectly to a chainring or a belt pulley of a traction drive for driving a driven wheel of the vehicle.

The detection device 10 serves to detect a relative rotation of the first rotating section 12 and the second rotating section 16 . To this end, the detection device 10 includes a number of first coupling rods 24, each having a first end 25a and a second end 25b. The first ends 25a are fixedly connected to the first rotating portion 12 . The second ends 25b are fixedly connected to the second rotating portion 16 . To put it more precisely, the coupling rods are designed as rods that are essentially inelastic in the longitudinal direction, but which can be bent like cantilevers relative to their respective connection to the first rotary section 12 or the second rotary section 16 .

In the 1 until 3 it is shown that the first coupling rods 24 are each aligned parallel to the longitudinal direction 20 . The first coupling rods 24 are arranged neither coaxially to the first axis 14 nor coaxially to the second axis 18 . Rather, the first ends 25a are arranged in a circle, evenly spaced from each other, as shown in FIG 3 is shown. The circle has a diameter D, which can be in a range from 10 to 25 mm, in particular in a range from 12 to 20 mm.

In the present case, the number of first coupling rods 24 is exactly 10 (ten). In other words, the first coupling rods 24 are evenly spaced from one another by 36° in the circumferential direction. However, the number of first coupling rods 24 can generally be in a range from 5 to 20, in particular in a range from 8 to 12.

The first coupling elements 24 are all arranged eccentrically to the first axis 14 and the second axis 18 .

The first rotating section 12 and the second rotating section 16 are coupled to each other by the plurality of first coupling rods 24 in a basic position, as shown in FIGS 1 until 3 is shown. In the basic position, the first coupling rods 24 are not elastically deflected.

In the 4 and 5 a position is shown in which the second rotary section 16 is rotated relative to the first rotary section 12 by an angle α. This leads, as is particularly the case in 4 can be seen, to the fact that the first coupling rods 23 are deflected obliquely, so that they are each arranged at an oblique angle in relation to the longitudinal direction 20, this oblique angle in 4 is shown at β. In the present case, such oblique angles are always measured when viewed perpendicularly to the respective axis 14, 16, etc.

It goes without saying that the ends 25a, 25b, which are in 4 and 5 are not shown in more detail for reasons of clarity, continue to emerge vertically from the respective rotary sections 12 and 16, but the coupling rods in the area in between are deflected, so that they are skewed in relation to the axes 14, 16.

In 3 a coupling rod 24a is shown by way of example in the assumed basic position at 0°, ie in a position in which the crank K2 points vertically upwards, for example.

In the comparison of the 5 the crank K2' is deflected by the angle α, corresponding to about 36°, so that the coupling rod 24a which is in 3 shown at 0° is now positioned at the position at about 36° (=α) as shown in Fig 5 at 24a' is shown.

The first coupling rods 24 are formed from a resilient material, for example spring steel or the like. Accordingly, a relative rotation between the first rotary section 12 and the second rotary section 16 can only take place when a moment is applied to one of the rotary sections 12, 16, which is supported in some form on the other rotary section. The applied moment then leads to the relative rotation of the rotary sections 12, 16, in which the first coupling rods 24 are elastically deflected. As soon as the torque is no longer present, the detection device 10 therefore returns to the basic position due to the elasticity of the first coupling rods 24, as in FIGS 2 and 3 is shown.

Due to the twisting of the rotary sections 12, 16, the relative distance between the rotary sections 12, 16 is changed due to the fact that the first coupling elements 24 are designed to be essentially inelastic in the longitudinal direction. This leads to an axial offset A of the second rotary section 16, since the first rotary section 12 is mounted axially.

The axial length of the first coupling elements 24 is in a range from 10 mm to 60 mm, in particular in a range from 10 mm to 30 mm.

The detection device 10 also includes a sensor arrangement 26. The sensor arrangement 26 has a first sensor section 28 in the form of a magnetic sensor wheel 28 which is fixedly connected to the second rotary section 16. The outer circumference of the sensor wheel of the first sensor section 28 can be smooth. However, the sensor wheel 28 is preferably formed with an incremental section 30, the sensor wheel having a plurality of teeth, as is shown in FIGS 3 and 5 you can see.

In 2 1 shows that the first sensor section 28 is in an axial neutral position N in the basic position.

After rotation of the rotary sections 12, 14, the second rotary section 16 migrates towards the first rotary section 12, so that the relative rotation of the rotary sections 12, 16 results in an axial offset of the second rotary section 16, as shown in 4 is shown at A (as the difference of a travel to the neutral position N as shown in 2 is shown).

The sensor assembly 26 further includes a second sensor portion 32 fixed to the housing 34 . The second sensor section 32 is designed to measure the axial offset A. The second sensor section 32 can be a Hall sensor or an inductive sensor, for example.

In general, however, it is also possible to use any other type of sensor. In any case, the detection of the axial offset A is preferably contactless, it being possible for the second sensor section 32 to be electrically connected to a power supply via the housing 34 . However, the first sensor section 28 is preferably a passive sensor section, such as a magnetic sensor section, such that it is not necessary to power the first sensor section 28 . It is therefore not necessary to provide sliding contacts.

Like it in the 2 and 4 As shown, the second sensor portion 32 is preferably bow-shaped and encompasses the first sensor portion 28, such that the second sensor portion 32 may include two sensor elements, as will be explained below.

In the embodiment of 1 until 5 For example, the detection device 10 has two rotary portions 12, 16, one of which is axially fixed and the other of which is mounted for axial displacement with respect to the other.

In the 6 until 8th 1 is shown another embodiment of a sensing device 10A which is generally similar to the sensing device described above and includes the first pivot portion 12 and a second pivot portion 16A coupled together by a plurality of first link rods 24A, similar to the first embodiment.

However, the detection device 10A additionally has a third rotary section 40 which rotates about a third axis 42 (see FIG 7 ) is rotatably supported on the housing by means of a third radial bearing 44 with respect to the housing 34A. The third axis can be radially offset from the second axis 18, but is preferably arranged coaxially thereto.

The third rotary section 40 is axially supported with respect to the housing 34A by means of a further axial bearing 46, just as the first rotary section 12 is axially supported by means of the axial bearing 22 with respect to the housing 34A.

The third pivot portion 40 is connected to the second pivot portion 16A via a plurality of two th coupling rods 48 coupled, which are constructed the same as the first coupling rods 24A.

More specifically, first ends 49a of the second connecting rods 48 are fixedly connected to the third rotating portion 40, and second ends 49b of the second connecting members 48 are fixedly connected to the second rotating portion 16A.

Just like the first coupling elements 24A, the second coupling elements 48 are arranged with their respective ends on a circle which is coaxial with the respective axis 18A, 42.

The third axis 42 is preferably coaxial with the second axis 18A and the first axis 14, as also shown in FIGS 6 until 8th is shown.

In the detection device 10A of FIG 6 until 8th the first coupling rods 24A and the second coupling rods 48 in the basic position shown are arranged from the outset at a respective oblique angle skewed at a respective oblique angle to the first axis 14 . To be more precise, the first coupling elements 24A and the second coupling elements 48 are essentially mirrored in relation to a radial plane that runs through the second rotary section 18A, such that the oblique angles β1 of the first coupling elements 24A are identical in magnitude to the oblique angle β2 of the second coupling elements 48, but with a different sign.

The first rotating section 12 and the third rotating section 40 can be rotated relative to one another without the first rotating section 12 and the third rotating section 40 being forced to be displaced axially relative to one another.

Rather, such a relative rotation between the first rotating section 12 and the third rotating section 40 inevitably results in an axial offset of the second rotating section 16A in relation to the housing, which can be detected by means of a sensor arrangement 26, which can be constructed similarly to the embodiment in FIG 1 until 5 .

In 8th such an axial offset A is shown schematically. The rotation of the first rotary section 12 and the third rotary section 40 has caused the first coupling elements 24A to be aligned more straight, which leads to a changed first oblique angle β1′ of 0° degrees. On the other hand, the oblique angle β2' of the second coupling rods 48 has increased. As a result, the second rotary section 16A has moved away from the first rotary section 12 in the longitudinal direction 20 and has approached the third rotary section 40 in the longitudinal direction 20 .

This makes it possible to mount both the first rotating section 12 and the third rotating section 40 in the axial direction, so that an approach to other components of the pedal crank arrangement or a bicycle is simplified. The second pivot section 16A is preferably completely freely movably suspended between the pivot sections 12, 40 by means of the first tie rods 24A and the second tie rods 48.

In 9 a preferred embodiment of a sensor arrangement 26 is shown.

The sensor assembly 26 includes a first sensor portion 28 in the form of a sensor wheel, similar to the previously described embodiments. The sensor wheel 28 is preferably equipped with an incremental section 30 on its outer circumference.

The second sensor section 32 is designed as a bracket that overlaps the first sensor section 28 . A first sensor element 50 and a second sensor element 52 are fixed to the second sensor section 32, specifically on axially opposite sides of the first sensor section 28.

The sensor elements 50, 52 can be Hall sensors, for example, which are fed by means of a supply voltage V _S and are connected to an unspecified ground connection. Furthermore, each of the sensor elements emits a voltage V ₁ or V ₂ as a function of the approach to the sensor wheel 28, which is supplied to an evaluation unit 54, which is designed, for example, as a bridge circuit for amplifying the sensor signal.

The evaluation unit 54 outputs the angle of rotation α measured by means of the axial offset A. The evaluation unit 54 preferably also outputs an angular velocity w, or a rotational speed proportional thereto, or a relative or absolute rotational position of the second rotating section 16A.

reference list

10

Device for detecting relative rotation

12

first turning section

14

first axis

15

first radial bearing

16

second turning section

18

second axis

19

second radial bearing

20

longitudinal direction

22

Thrust Bearing (12)

24

first connecting rods

25a

first end

25b

second end

26

sensor arrangement

28

first sensor section (sensor wheel)

30

incremental section

32

second sensor section

34

Housing

40

third turning section

42

third axis

44

third radial bearing

46

further axial bearing

48

second connecting rods

49a

first end

49b

second end

50

first sensor element

52

second sensor element

54

Evaluation unit/bridge circuit

T

Pedal crank assembly for a bicycle

K1

crank 1

K2

crank 2

R

direction of drive rotation

D

diameter circle (24)

A

axial misalignment

a

Twisting angle 12/16

β

oblique angle 24

β1

first oblique angle 24A

β2

second oblique angle 48

ω

Angular Velocity/RPM/Rotational Position

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• WO 9905493 [0003]
• DE 102008027719 A1 [0004]
• EP 2386844 A1 [0005]
• DE 102018107416 A1 [0006]
• DE 102020100319 A1 [0007]

Claims (15)

Device (10) for detecting a relative rotation between a first rotating section (12) and a second rotating section (16), which are spaced apart from one another in a longitudinal direction (20), - wherein the first rotary section (12) can be rotated about a first axis (14) which is arranged parallel to the longitudinal direction (20), - wherein the second rotary section (16) can be rotated about a second axis (18), - wherein the first rotating section (12) and the second rotating section (16) are coupled to one another via at least two first coupling elements (24) which are designed to be essentially inelastic in the longitudinal direction (20) and at least one of which is neither coaxial to the first axis ( 14) is still arranged coaxially to the second axis (18), such that a relative rotation of the first rotating section (12) and the second rotating section (16) necessarily results in a relative axial offset (A) between the first rotating section (12) and the second rotating section (16) leads, and - With a sensor arrangement (26) which detects the axial offset (A). detection device claim 1 wherein the first coupling members (24) each have a first end (25a) fixedly connected to the first pivot portion (12) and a second end (25b) fixedly connected to the second pivot portion (16). detection device claim 2 , wherein the first ends (25a) of the first coupling elements (24) are arranged on a circle coaxial to the first axis (14) and/or wherein the second ends (25b) of the first coupling elements (24) are arranged on a circle relative to the second axis ( 16) are arranged in a coaxial circle. Detection device according to one of Claims 1 - 3 , wherein the detection device (10) has a third rotary section (40) which can be rotated about a third axis (42) which is arranged parallel to the longitudinal direction (20) and which is connected to the second rotary section (16) via at least two second coupling elements (48) are coupled, which are designed to be essentially inelastic in the longitudinal direction (20) and at least one of which is arranged neither coaxially with the third axis (42) nor coaxially with the second axis (18) in such a way that a relative rotation of the third rotating section (40) and the second rotating section (16) inevitably leads to a relative axial offset (A) in the longitudinal direction between the third rotating section (40) and the second rotating section (16). detection device claim 4 wherein the second coupling members (48) each have a first end (49a) fixedly connected to the third pivot portion (40) and a second end (49b) fixedly connected to the second pivot portion (16). detection device claim 5 , wherein the first ends (49a) of the second coupling elements (48) are arranged on a circle coaxial to the third axis (42) and/or wherein the second ends (49b) of the second coupling elements (48) are arranged on a circle relative to the second axis ( 18) are arranged in a coaxial circle. Detection device according to one of Claims 1 - 6 , wherein the first coupling elements (24) are first rod-shaped elements and/or wherein the second coupling elements (46) are second rod-shaped elements. detection device claim 7 , wherein the first rod-shaped elements (24A) in a basic position are each arranged at a first oblique angle (β1) skew to the first axis (14) and to the second axis (18) and/or wherein the second rod-shaped elements (48) in a basic position are each arranged at a second oblique angle (β2) skewed to the third axis (42) and to the second axis (18). detection device claim 7 or 8th , wherein the first coupling elements (24A) and the second coupling elements (48) are essentially mirrored in relation to a radial plane that runs through the second rotary section (18), such that the first rotary section (12) and the third rotary section (40) can be rotated relative to one another without the first rotary section (12) and the third rotary section (40) being forced to be displaced axially relative to one another. Detection device according to one of Claims 1 - 9 , wherein the sensor arrangement (26) has a first sensor section and a second sensor section (42), the first sensor section (28) being fixed to the second rotary section (16; 16A) and the second sensor section (32) being fixed to a housing (34 ) is fixed. detection device claim 10 , wherein the first sensor section (28) has a magnet and / or wherein the second sensor section (32) has at least one Hall sensor or inductive sensor. detection device claim 10 or 11 , wherein the second sensor section (32) has at least two sensor elements (50, 52), which are arranged on axially opposite sides of the first sensor section (28). detection device claim 12 , wherein the two sensor elements (50, 52) are connected in a bridge circuit (54). Detection device according to one of Claims 10 - 13 , The first sensor section (28) having an incremental section (30) by means of which a rotation of the second rotary section (16; 16A) can be detected. Pedal crank assembly for a human-powered vehicle having a first crank (K1), a second crank (K2) and a detection device (10) according to one of Claims 1 - 14 wherein the first crank (K1) is non-rotatably connected to the first rotary section (12) and wherein the second crank (K2) is non-rotatably connected to the second rotary section (16) or, if the detection device (10) has a third rotary section (40). , is connected to the third rotary section (40.

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